Air bag
An air bag has a large occupant-receiving area when expanded. The air bag has: a top chamber, which expands along a ceiling part; a first chamber, which expands downwards and rearwards from the rear part to the top chamber; a second chamber continuous from the lower part of the first chamber, the second chamber expanding downwards; and a third chamber continuous from the lower part of the second chamber, the third chamber expanding forwards. The expanded first chamber restrains the head of an occupant, and the second chamber restrains the chest to the trunk.
1. An airbag which is adapted to be inflated in front of an occupant seated in a seat by gas from an inflator, the airbag comprising:
a first chamber that is inflated downward and rearward from a vehicle interior ceiling portion;
a second chamber that is continuous from a lower portion of the first chamber and that is inflated forward; and,
a first tether that is connected between a connection portion of the first chamber and the second chamber or a peripheral portion of the connection portion, and a part in front of the first chamber.
2. The airbag according to claim 1 ,
wherein the connection portion of the first chamber and the second chamber is a bending point of the airbag in a state where the airbag is inflated.
3. The airbag according to claim 1 , comprising:
a second tether that is connected between the second chamber and a part in front of the first chamber.
4. The airbag according to claim 1 , further comprising:
a second tether that is connected between the second chamber and the part in front of the first chamber; and
a top chamber that is inflated along the vehicle interior ceiling portion,
wherein the first chamber is continuous from a rear portion of the top chamber, and
wherein an upper end of the first tether and an upper end of the second tether are continuous from a front portion of the top chamber.
5. The airbag according to claim 4 ,
wherein the top chamber is fixed to the vehicle interior ceiling portion at at least two places in a front-rear direction.
6. The airbag according to claim 4 , further comprising:
a third chamber that is provided between the top chamber and the first chamber.
7. The airbag according to claim 6 , further comprising:
a third tether that is connected between the front portion of the top chamber and a connection portion of the first chamber and the third chamber.
8. The airbag according to claim 7 , comprising:
a fourth tether that is connected between an intermediate portion of the second chamber in a front-rear direction, and an upper portion of the first chamber or a portion in front of the upper portion.
9. The airbag according to claim 1 ,
wherein a gas flow path width is narrowed in the connection portion of the first chamber and the second chamber.
10. The airbag according to claim 1 , further comprising:
a plurality of tethers that extends radially downward from the vehicle interior ceiling portion in the state where the airbag is inflated,
wherein each of the tethers of the plurality of tethers is continuous to a predetermined portion of the airbag.
11. The airbag according to claim 1 ,
wherein an intersection angle between a rear surface of the first chamber and a horizontal surface is 25° or more and 65° or less in the state where the airbag is inflated.
12. The airbag according to claim 1 ,
wherein in the state where the airbag is inflated, a center portion in a left-right direction of a rear surface of the first chamber is a concave portion which is recessed forward from left and right of the concave portion.
13. The airbag according to claim 1 ,
wherein in the state where the airbag is inflated, a center portion in a left-right direction, as well as a lower portion in an upper-lower direction of a rear surface of the first chamber, is a convex portion which protrudes rearward from left and right of the convex portion.
14. The airbag according to claim 1 ,
wherein a left-right width of the first chamber is larger than a left-right width of the second chamber.
15. An airbag which is adapted to be inflated in front of an occupant seated in a seat by gas from an inflator, the airbag comprising:
a first chamber that is inflated downward and rearward from a vehicle interior ceiling portion;
a second chamber that is continuous from a lower portion of the first chamber and that is inflated downward; and
a third chamber that is continuous from a lower portion of the second chamber and that is inflated forward; and,
a first tether that is connected between a connection portion of the first chamber and the second chamber or a peripheral portion of the connection portion, and a part in front of the first chamber.
16. The airbag according to claim 15 , comprising:
a second tether that is connected between the third chamber and a part in front of the first chamber.
17. The airbag according to claim 16 ,
wherein the second tether is continuous to an intermediate portion of the inflated third chamber in a front-rear direction, and
wherein a third tether is provided such that the third tether is connected between a front portion of the third chamber and a connection portion of the second chamber and the third chamber.
18. The airbag according to claim 17 ,
wherein in a state where the airbag is inflated, the front portion of the third chamber is located higher than the intermediate portion in the front-rear direction of the third chamber connected to the second tether.
19. The airbag according to claim 16 ,
wherein the airbag comprises a top chamber that is inflated along the vehicle interior ceiling portion,
wherein the first chamber is continuous from a rear portion of the top chamber, and
wherein an upper end of the first tether and an upper end of the second tether are continuous from a front portion of the top chamber.
20. The airbag according to claim 19 ,
wherein a gas flow path width is narrowed in a connection portion of the top chamber and the first chamber.
21. The airbag according to claim 15 ,
wherein a gas flow path width is narrowed in the connection portion of the first chamber and the second chamber and a gas flow path width is narrowed in the connection portion of the second chamber and the third chamber.
22. The airbag according to claim 15 ,
wherein the third chamber is inflated such that a front portion of the third chamber abuts against a rear surface of a front seat.
23. The airbag according to claim 15 ,
wherein the connection portion of the first chamber and the second chamber is adapted to be located below a head of the occupant.
24. The airbag according to claim 15 ,
wherein a center portion in a left-right direction of a rear surface of the first chamber is a concave portion which is recessed forward from left and right of the concave portion.